Tanzania presidency reported elephant and rhino populations have begun to recover after a government crackdown dismantled organized criminal networks involved in industrial-scale poaching and transporting the ivory to China.

A influential Chinese businesswoman running a poaching network on industrial scale, dubbed the “Ivory Queen” was sentenced to 15 years in prison by a Tanzanian court in February for smuggling the tusks of more than 350 elephants, weighing nearly 2 tonnes, to Asian countries. Yang Feng Glan had been charged in 2015 along with two Tanzanian citizens with smuggling 860 pieces of ivory between 2000 and 2004 worth $5.6 million.

“As a result of the work of a special task force launched in 2016 to fight wildlife poaching, elephant populations have increased from 43,330 in 2014 to over 60,000 presently,” the presidency said in a statement this week, underlining the success of the case as a government victory over illicit ivory traffic.

The number of rhinos, an endangered species, had increased from just 15 to 167 over the past four years, the report says.